Reversing switch



F. HOFFNER.

REVERSING SWITCH.

APPLICATION FILED JUNE 11, 1921.

1,412,941, I Patenfgd Apr. 18, 1922.

' UNITED STATES.

rm: Hosanna, or anssnuaa, MICHIGAN.

' nnvnasme swrrcn.

1 '0 all whom it may concern:

Be it known that I, FRANK HOFFNER, a citizen of the United States, residing at Bessemer, in the county of Gogebic and State of Michigan, have invented certain new and useful Improvements in Reversing Switches, of which the following is a specification, reference being had to the accompanying drawings. 1

This invention relates to reversing switches and has for a particular object the provision of a semi-automatic reversing switch for use in connection with motors.

An important object of the invention is to provide a switch of this character whereby the direction of current through the motor may be reversed as to the armature or field thereof by employing in the feed wire to the motor a differential current.

A further object of the invention is to provide a switch of this character which embod- '1 of the switches to closed, position being op posed by springs of varying strengths whereby a given current will actuate one of. the switches, and a current of different strength will actuate the other of the switches. A construction such as set forth above will, as is obvious to those familiar with the art, permit of a remote control of the motors of a car or of a plurality of cars.

A further object of the invention is to provide in a switch of the character above set forth and embodying a pair of relay switches, means whereby the movement of either of the switches to the active position will render the magnet coil of the other of the switches inactive and the switch accordingly inoperative.

Other objects and advantages of the invention will become apparent throughout the course of the following description.-

In the accompanying drawings wherein for the purpose of illustration is shown a preferred embodiment of my invention and wherein like reference characters designate like parts throu hout:

Figure 1 is a ront elevation partially diagrammatic, showing a switch constructed in accordance with my invention and circuit therefor; 0

Figure is a slde elevation showmg the Specification of Letters Patent.

PATENT-OFFICE.

. Patented Apr. 18, 1922-.

Application filed June 11, 1921. Serial No. 476,801.

main feed wires from a suit-able source of current, the wire 11 beinggrounded. The wire 10 is in circuit through a rheostat R with a wire l0 'which connects with two contacts of a switch S. The switch S embodies a th11 'd contact to which is connected a shunt clrcult from the wire 10, which circuit contalns resistance coil 12. In the present instance this shunt circuit is shown as connected with the wire 10 at the point of its connection with the usual blow-out coil C provided in controllers. It is here pointed out that the rheostat R, blow-out coil C and switch S form thenormal parts of control box-of the type usually employed in electric railway control, theswitch S corresponding to the reversing switch thereof. This switch embodies two poles which, when in one position, engage with the contacts connected with the wire 10" from the rheostat R, and which when in the other position connect with the wire 1O throu h one of the contacts, and with the shunt clrcuit containing the resistance element '12 through the third contact.

send a current through the feeder 10. If,

however, the switch is shifted to the position shown in dotted lines and the rheostat blade is not engaged with any of its contacts, a small current will flow through the shunt circuit to the feeder 10, the amount of current passing through the feeder 1O when the switch is in the position shown in dotted lines being less than the amount of current which flows through the feeder 10 when the switch S is in the position shown in solid lines, and the blade of the rheostat engaged with the contact thereof which places in circuit the greatest amount of resistance to the passage of current.

A control of the type hereinbefore set forth may be employed either at the leading car of a train of cars or in a control house such as is commonly employed in mines where ore cars and. the likeare shifted upon 13 formed of insulating material and havin mounted thereupon a pair of rela switc units A and B. Each relay unit and B embodies a compound wound electro-magnet 14 having a shunt winding 14 and a series winding 14". These electro-magnets,

when energized, attract arms 15 secured to or formed upon rotatably mounted shafts 16. The movement of the arm 15 toward the electro-magnet is opposed by a spring 14 through medium of a plunger 14 engaging the arm, these springs and plungers preferably being contained within the core of the elect-ro-magnet; The spring 14 of the electro-magnet 14 of the relay A is stronger than that of the electro-magnet 14 of the relialy B for a purpose hereinafter to appear. ach shaft 16 has secured thereto an insulatory block 17 having switch fingers 18 and 19 secured thereto. These fingers 18 and 19 coact with contacts 18 and 19 carried by the board 13 engaging therewith when the electro-magnets 14 of their particular relays are energized.

Each insulating block 17 has likewise secured thereto a finger 20. The finger 20 of the relay A coacts with the finger 20 carried by the board 13 and grounded, the finger engaging the coacting finger 20" when the blades 18 and 19 are separated from their contacts 18 and 19. To the finger 20 of the relay A, the terminal of the shunt coil 14 0f the relay B is connected, and it will accordingly be seen that when the fingers 18 and 19 of the relay A are in engagement with their contacts the shunt coil of the relay B has its ground circuit broken and is accordingly de-energized. The ground circuit of the shunt coil 14 of the relay A is completed through a spring finger 20 coacting with the grounded stationary contact 20, the spring finger normallybeing in engagement with the stationary contact 20. When, however, the fingers 18 and 19 of the relay B move into engagement with their contacts 18. and 19, the finger 20 thereof engages with the spring finger 20", moving the same out of engagement with the stationary contact 20, breakingthe ground circuit to the shunt coil 14* of the relay A and de-energizing the same.

The feeder 10 is connected with each contact 18 of the relays A and B by branch wires 21. The contacts 18 have a shunt connection with the shunt winding 14 of the coil 14, as indicated at 22. Each canted? 9 of the relay units A and B is-connected with the series winding of its respective electromagnet by a wire 23. The other terminals of the series winding 14 of the coils of the magnets 14 are connected to a wire 24 leading to the field winding of the motors and through this winding to theground. The

switch S is in the position shown in solid lines in the diagrammatic view in Figure l, the full stren th of the current is sent through the fee er 10 'and branches 21 thereof to the shunt connections 22, and accord ingly to the-shunt winding of the electromagnets 14. With the full strength of the current which is sufficient to attract the arm 15 of the relay A against the action of the spring 14, the arm 15 is drawn upwardly so sharply in this relay that the electromagnet of the relay unit B has not sufficient time to work, and as this arm is drawn up it breaks the shunt circuit through the relay electro-magnet of the relay B, rendering the same inoperative, the arm 20 of the relay unit A disengaging from its contact 20*. The attraction of the arm 15 brings the fingers 18 and 19 into engagement with their contacts 18 and 19 in the relay unit A, and current accordingly flows from the feeder 1O through the branch 21 to the contact 18 through the contact finger 18, and by wire 25 to one side of the armature, out of the armature at the opposite side, through the branch wire 25 of the wire 25, connecting the finger 18 of the relay unit B with the motor lead through the branch 25 thereof to the finger 19 of the unit A, through the contact 19, wire 23, winding 14 and wire 24 to the field of the motor and to the ground, rotating the motor in one direction.

To reverse the direction of the motor or motors the current is first broken, causing the switch fingers of the unit A to move to inoperative position under the action of the spring 14 thereof. The switch S is then moved to connect above the wire 10 and the shunt circuit containing the resistance to the relay magnet 14 of the unit A. The current now flows from the feeder 10 through the other branch 21 to the contact 18 of the unit B, through the finger 18 and wire 25,connecting the same to the armature of the motor; out of the opposite side of the motor through the wire 25, connecting the same with the finger 18 of the unit A, through the branch wire 25 0f this wire 25 to the fin er 19, from the finger to the contact 19, t rough wire 23 to the field winding 14" of the electro-magnet 14 of the unit B, and through this winding to the wire 24, field of the motor and to the ground.

It will be observed that in each instance the movement of the fingers of either of the units renders it impossible to move the fingers of the other unit by breaking the shunt circuit through the electro-magnet thereof. It will of course be obvious that the formal showing of the manner of providing currents of different strengths for the selective actuation of. the electro-magnet units of the relays may be accomplished by any desired arrangement, the construction shown being preferred by reason of its adaptability to the controllers at present in use in electric railway systems. obvious that the specific arrangement hereinbefore set forth is capable of many and varied changes, the drawings being largely diagrammatic. I accordingly do'not limit myself to the specific structure hereinbefore set forth except as hereinafter claimed.

What is claimed is: g

1. The combination with a circuit and means for altering the E. M. F. of the circuit, of a reversible motor embodying the usual field and armature windings, one terminal of one of said windings being electrically connected with one terminal of the circuit, a air of multi-blade relay units of different M. F. requirements arranged in parallel and each connected with the other terminal of the circuit, said relay units being oppositely connected with the terminals of the other of said windings and similarly connected with the first mentioned winding.

2. The combination with a circuit and means for altering the E. M. F. of the circuit, of a reversible motor embodying the usual field and armature windings, one terminal of one of said windings being electrically connected with one lead of the circuit, a air of two blade relay units ofdifierent E. F. requirements arranged in parallel and each havinga contact connected with the other branch of the circuit, the blades of each of said units being in series with the other motor winding, the other contact of each unit being in series with the coil of its unit, the first named contact being shunt-connected with the coil of its unit, a connection between the coil of" each unit and the first named, motor winding, and means actuated It will furthermore beby the efiective ener izing of either of said units for'breaking t e shunt-circuit of the coil of the other of the units. I

3. The combination with a circuit and means for altering the E. M. F. of the circuit, of a reversible motor embodying the usual field'and armature windings, one ter minal of one of said windings being electrically connected with one lead of the circuit, a pair of two-blade relay units of different M M. F. requirements arranged in parallel and each having a contact connected with the other branch of. the circuit, the blades of each of said units being in series with the other motor winding, the other contact of each unit being in series with the coil of its unit, the first named contact being shunt-connected with the coil of its unit, a connection between the coil of each unit and the first named motor winding, and means actuated by the effective energizing of either of said units for breaking the shunt-circuit of the coil of the other of the units, the corresponding blades of said units 'being connected to opposite terminals of the last named motor winding.

4:. The combination with a circuit and means for altering the E. M. F. of the circuit, of a reversible motor embodying the usual field and armature windings, one terminal of one of said windings being electrically connected with one terminal of the circuit, a pair of multi-blade relay units of difi'erent E. M. F. requirements arranged in parallel and each connected with the other terminal of the circuit, said relay units being oppositely connected with the terminals of the other of said windings and similarly connected with the other terminal of the first mentioned winding, the. electro-magnetic elements of saidv units being shunt-connected with said circuit, the effective energizing of either of said elements breaking the circuit of the other of said elements.

5. The combination with a circuit and means for altering the E. M. F. of the circuit, of a reversible motor embodying the usual field and armature windings, one terminal of one of said windings being electrically connected with one terminal of the circuit, a pair of multi-blade relay units arranged in. parallel and each connected with the other terminal of the circuit, said relay units having the blades thereof oppositely connected with the terminals of the other of said windings, and the coils thereof similarly connected to the other terminal of the first mentioned winding, and yieldable elements of different strength resisting the movements of the blades of said units.

6. The combination with a reversible motor, of a switch comprising a pair of multiblade relay units reversely connected with the motor, said units each embodying a compound wound electro-magnetic element, one

of said windings of each of said units being normally energized, and means operated by the closing, of the blades of either of said units for tie-energizing the eleetro-magnetic element of the other unit and for completing a circuit through the other winding of its respective electro-magnetic element.

7. The combination with a reversible motor, of a switch comprising a pair of multiblade relay units reversely connected with the motor, said units each embodying a compound wound electro-magnetic element, one of said windings of each of said units being normally energized, and means operated by the closing of the blades of either of said units for de-energizing the electro-magnetic element of the other unit and for completing a circuit through the otherv winding of its respectlve electro-magnetic element, and remote control means for selectively energizmg said electro-magnetic elements.

8. The combination with a reversible motor, of a switch comprising a pair of multiblade relay units reversely connected with the motor,- yieldable means of different reslstive strength resisting the closing of the blades of said units, and means operated by the closing of the blades of either of said units for rendering the other unit inoperaive.

In testimony whereof I hereunto afiix my signature.

FRANK HOFFN ER. 

